Essential Crystal Spinner Gyro Ball | Grip Strengthener for Forearms, Wrist & Hands | String Start Design, Up to 18,000 RPM | Portable Wrist Trainer & Workout Equipment | Ideal for Desk Workers, Athletes & Musicians

good product, not hard to use, easy once you get the hang of it and good hand physical therapy.

I was one of the “tough customers” as far as learning technique goes. It took me 4 hours. I’m not even kidding. That thing people say about swishing a wine glass made no sense to me. I don’t know how you people swish your glasses but unless you’re balancing the base of your glass on an open palm (which is weird!) it meant nothing to me. Still, after 4 hours of YouTube tutorials, I got it! Some of the problem for me was that my hands were so weak that I was underestimating how slow and wide and gentle my turns of the ball would need to be.I won’t lie - I got it so that I could text faster, play games longer, and wear my smart watch on a tighter loop. Nerdiest reasons ever. But it works! My forearm size shrunk literally overnight and I was wearing my watch so much more comfortably. And instead of wearing out after 2-3 hours of Call of Duty or Rocket League, I was going 6-8 hours and playing better than I have in my life.I play 6-8 hours on weekends all the time, but toward the end of that I start breathing a little more, and making more conservative plays, and my fingers hit the wrong button or I hit it too fast or too slow and feel like my mind is getting bored or confused.It turns out, a lot of times MY HANDS WERE TIRED! I’m just not used to thinking of my hands as needing that much babysitting or conscious thought in taking care of them. But now that I am giving them exercise, it’s like I gained a new sense, similar to sight or smell, except this one is for hand fatigue. It’s another HP meter running in my brain of how well my hands are doing. When it gets low I use this ball for a little bit and I’m aces for another several days.As a nerdy type, I never really saw the appeal in working out, it felt like just some annoying motions that you repeat while feeling bored to tears. But this ball takes some thought to control and keeps me amused.I actually got the Diablo Evo Autostart Pro from Powerball as an upgrade to this because I liked it so much. Keeping track of the gyroscopic motion is a challenge, like a game in itself, and that makes exercise less boring to me.To people who aren’t as sheltered as I am: Yeah, I know this review comes off as “Wow, this idiot sounds like they just discovered America!” Yeah, you’re right. But there’s a lot of people like me who don’t try new things until they’re coaxed into it, and I’m glad there are products like this, which help us introduce us to new lifestyles. :)

First, let me say that I got this as a gift. I had been eyeing it myself for well over a year and just couldn't pull the trigger because this really doesn't look like any other training tool out there. Still, I like new and I'm willing to try just about anything once. So I was stuck in limbo until my wife decided that it had hung out in the wish list long enough.My impression was that this was marketed as a grip strengthening tool of some sort. That's probably a miss on the part of the marketing department. What it does is more like mud running for the forearm muscles. It's an endurance trainer with resistance, and actually it does a good job at this once you catch the drift. The circular motion that the wrist must perform to make this work seems like it would also be good for rehab or warm ups if done in shorter durations and at slower speeds. So, in the right context this becomes a great tool. But it isn't really a grip strengthening tool unless you have the strength of a toddler.How it works: essentially this is a fly wheel. As RPMs increase that fly wheel resists changes of direction (centrifugal forces, Newtonian physics... Science!). This is what creates the resistance aspect. The circular motion of the wrist keeps the fly wheel spinning which creates an endurance aspect. Stop rotating your wrist and the fun ends as the fly wheel slows.Bottom line, it's not a bad little fitness gadget, but probably has limited use outside a physical therapy application unless you are in a sport where lots of forearm endurance is key... Like rock climbing. There isn't time to do everything, and what time you have is probably better spent doing something else. That's why I gave it 4 stars, fun and works... But what's the point?

I had an old Dynabee back in the late 1970s - this one is a bit heavier, feels much more precise and solid, and works really well. The little string pull starters are great if you can't get it started easily by itself - I have a pretty good success rate spinning it up by hand then teasing it up to speed gently. I find that it is quiet enough to watch TV while using it. You can control the resistance by how much effort you put in, and when you get going hard, the resistance is strong enough to get a good hand/forearm workout very quickly. From reading other's comments, I see there are a few different grips/positions that I have not tried, so I look forward to those. I also found, to my slight surprise, that one hand requires a lot more focus and attention than the other, and I can't really sustain it well with that hand, so that is another good goal to work on!

This is the string-started version of the spinner. It is very difficult to get going even after several tries. Each try requires a minute to thread the string around the inner sphere. When I can get it going at the right speed, it's a challenge to keep it going for even half a minute. I'm coming back to see if there is another model that would be more usable, but the lineup of models and features is very confusing, even on their website. Prices vary widely with no clear explanation between models. What is also confusing is that there are several similar-named brands which all appear to be the exact same product. It's hard to trust what it is I'm buying.